HVLP Curiosity

I was cleaning my Earlex hvlp gun the other day and was wondering how the finish product gets sprayed out via the needle? I see there is an oriface at tip of needle but it seems obvious to me that the product doesn’t actually travel through the needle. So how does the mechanics of this work?

3 replies so far

If I’m understanding the question right, fluid travels up the pickup tube, through the “tunnel” in the gun body (in which the needle is inside of also. When you pull trigger the needle pulls back into the tip and fluid is pushed out through the tip around the needle. The more you pull trigger, the further back the tip travels allowing more fluid to escape out the tip. The air stream from the air cap thing blows onto the fluid stream causing it to break down/atomize into a spray. At least that’s my layman’s guess of how the thing works…

Is that close to what you were asking?

I don’t thing the tip of the needle has an actual orifice. It might be a dimple looking spot from manufacturing.

I think hotbyte has it right. The needle is not a needle, but it inserts into the orifice which is sized to the needle. Like he said, the further the needle is allowed to withdraw, the more product goes out around it where it is injected into the air flow that atomizes the product.